Pressure actuated device with concentric piston stem actuators

ABSTRACT

A high proof pressure device for either opening or closing a number of electrical circuits in response to a wide range of changing fluid pressures is provided with a switch for each circuit controlled by a flexible sensor common to concentric, switch actuating piston stems, all contained within a single envelope which is not only tamper proof and explosion proof but capable of protecting its components from adverse weather conditions.

United States Patent Hoyt 1451 Apr. 18, 1972 [54] PRESSURE ACTUATEDDEVICE WITH 2,975,251 3/1961 Beller et a1 ..200/8l.4 x CONCENTRIC PISTONSTEM 3,182,149 5/1965 Noakes ..200/83 s x ACTUATORS FOREIGN PATENTS ORAPPLICATIONS [721 Invent Shawnee M Kans' 1,218,588 6/1966 Germany..200/83 s [73] Assignee: W. E. Anderson, Inc.

Primary ExaminerRobert K. Schaefer [22] Elled' 1970 AssistantExaminer--Robert A. Vanderhye [2 1] Appl. No.: 91,979 Attorney-Schmidt,Johnson, Hovey & Williams 52 us. or ..200/81.4, 200/83 J, 200/83 s, [571ABSTRACT 200/81-5 Ahigh proof pressure device for either opening orclosing a [51] lnLCl ..H0lh35[34,H0|h 35/24 numb?r f electrical circuitsin response to a wide range of [58] Fleld of Search ..200/83 W, 83 S, 83SA, 83 J, h i fl id pressures is provided with a switch for each zoo/8L4153 v cult controlled by a flexible sensor common to concentric, I 6 R fd switch actuating piston stems, all contained within a single en- [5 1e erences velope which is not only tamper proof and explosion proof butUNITED STATES p capzhtle osf protecting its components from adverseweather I C011 1101'! 3,557,329 l/l97l Gorgens "200/83 S 2,982,8305/1961 Schaefer et al ..200/83 J X 5 Claims, 6 Drawing Figures 1\\\\\ I[86 I I I a6 /4 I 20 f l I 54 22: :1 i o I 90 72 I 62 l I I 1 F .t

PRESSURE ACTUATED DEVICE WITH CONCENTRIC PISTON STEM ACTUATORS Animportant object of my present invention is to provide within a singlehousing, a number of circuit controlling electric switches, common to asingle sensor such as a diaphragm that is sensitive to changing fluidpressures, and operably associated with a novel arrangement of switchactuating pistons.

Another important object of the instant invention is the provision of asimple, compact system of separate pistons, one for each switchrespectively, and operable successively upon progressive changes influid pressures acting on the sensor.

Still another object of the present invention is to provide an accurate,easily adjusted high pressure range assembly of parts for transmittingmovement of the pistons to the actuators of their respective switches.

A further object of my present invention is the provision in theaforementioned improvements of components that are capable ofwithstanding relatively high surge pressures to which the device. may besubjected when it is coupled in a system that subjects the sensorthereof to fluids under a wide range of varying pressures.

In the drawing:

FIG. 1 is a plan view of a pressure actuated device made in accordancewith the present invention, parts being broken away to reveal details ofconstruction;

FIG. 2 is a cross-sectional view taken on line 2-2 of FIG. 1;

FIG. 3 is a cross-sectional view taken on line 3-3 of FIG. 2;

FIG. 4 is a cross-sectional view taken on line 4-4 of FIG. 2;

FIG. 5 is a cross-sectional view taken on irregular line 5-5 of FIG. 2;and

FIG. 6 is a perspective view of one of the primary piston actuatedlevers illustrated in FIGS. 1-4 inclusive.

All of the components of the pressure actuated device illustrated in thedrawing are contained within a single envelope or housing broadlydesignated by the numeral 10 which includes an intermediate tubularportion 12 constituting the main body of the housing 10, a cup-like cap14 releasably attached to and closing one end of the body portion 12, aplug 16 removably mounted within the body 12 at its opposite end and aplate 18 releasably attached to the plug 16 exteriorly of the housing10. A sensor in the nature of a flexible diaphragm 20 is clamped betweenthe plug 16 and the plate 18 in sealing relationship thereto across acavity 22 within the inner face of the plate 18, across a port 24 in theplate 18 and communicating with the cavity 22 and across a continuousseal 26 recessed within the inner face of plate 18 and surrounding thecavity 22, it being understood that the diaphragm 20 is clamped tightlyagainst the seal 26.

A tubular fitting 28 screw threaded into the port 24 is adapted forconnection to a fluid pressure line (not shown), thereby subjecting thediaphragm 20 to the fluid itself as the seal 26 and the sealingrelationship of the diaphragm 20 to the plug 16 and plate 18 preventsuch fluid from escaping the cavity 22 for flow into the housing 10 orflow from between the plug 16 and the plate 18.

All of the components contained in the housing 10 are either supportedor guideddirectly or indirectly by the plug 16, certain of suchcomponents being mounted upon a panel 30 secured to the inner face ofthe plug 16 diametrically thereof and extending inwardly therefrom,terminating within the cap 14.

Plug 16 has a cavity 32 facing outwardly in opposed relationship to thecavity 22 and receiving a disk type piston 34 that is in turn providedwith a tubular stem 36 which is reciprocable within and therefore guidedby a central bore 38 in plug 16 and communicating with the cavity 32.

The outer face of the piston 34 has a recess 40 in opposed relationshipto the stem 36 which receives a second disk like piston 42 which, as inthe case of the piston 34, faces the diaphragm 20, and which is providedwith a stem 44 that is reciprocable within and therefore guided by abore 46 extending centrally through the stem 36.

A pair of primary levers 48 and 50 for stems 36 and 44 respectivelyextend diametrically across the inner face of the plug 16, the elongatedbar-like lever 48 having a central hole 52, as best shown in FIG. 6, forclearing the stem 44. A washer 53 loosely surrounding the stem 44 isinterposed between the proximal end of the stem 36 and a pair ofprotuberances 54, one on each side respectively of the hole 52.

Perforations 56 and 58 in the lever 48 receive bolts 60and 62respectively that are mounted on the plug 16 and extend inwardlytherefrom. A nut 64 on the bolt 62 and a similar nut (not shown) on thebolt 60 maintain the lever 48 spaced from the plug 16 and precludespring 66 from pressing the piston 34 against the diaphragm 20.

Spring 66 is coiled on the bolt 62 between the lever 48 and an adjustingnut 68 on the bolt 62. A nut 70 on the bolt 60 holds the lever 48 inplace but nut 70 is not drawn tightly against the lever 48 because thebolt 60, fitting loosely within the perforation 56, serves as a fulcrumfor lever 48 as the latter swings toward and away from the nut 64against the action of the spring 66.

The lever 50 which overlaps the lever 48 in crossed relationship theretois likewise provided with a pair of spaced perforations comparable tothe perforations 56 and 58 receiving bolt 72 and bolt 74 respectivelycomparable to bolts 60 and 62 respectively. A spring 76 coiled on thebolt 74 between adjusting nut 78 and lever 50 holds the latter against aspacer 80 between plug 16 and lever 50, the spacer 80 maintaining thelever 50 spaced from the lever 48 and preventing spring 78 from pressingthe piston 42 against the diaphragm 20.

As in the case of the bolt 60, bolt 72 serves as a fulcrum for the lever50, the latter of which is held in place on the bolt 72 by a nut 82. Nocentral hole is provided in the lever 50 comparable to the hole 52,lever 50 instead being in direct alignment centrally thereof with theinner end of the stem 44.

Electric switches 84 and 86 corresponding to levers 48 and 50respectively are attached to the panel 30 on opposite sides of thelatter, the pigtail conductors 88 from the switches 84 and 86 passingfrom the housing 10 through a lateral stub conduit 90.

A pair of secondary levers 92 and 94 corresponding to switches 84 and 86respectively have a common fulcrum pin 96 traversing the panel 30.Levers 92 and 94 are provided with adjusting bolts 96 and 98respectively which bear against the corresponding bars 48 and 50.

Panel 30 is provided with graduations 100 adjacent washer 102 on bolt 62as an aid in determining the position of nut 68 in adjusting the tensionof spring 66 and a similar arrangement (not shown) is provided on theopposite face of the panel 30 as an aid in the adjustment of nut 78.

OPERATION If the device is positioned as illustrated in the drawings,pistons 34 and 42 will rest on diaphragm 20, but only a slight amount ofpressure in port 124 is needed to move stem 44 against lever 50 andwasher 53 against protuberances 54.

When the outer face of the diaphragm 20 is subjected to a predeterminedrise in fluid pressure within the fitting 28, the port 24 and the cavity22, it flexes away from the latter, acting on the piston 34 to shift thestem 36 inwardly along the bore 38 until the piston 34 bottoms out inthe cavity 32.

Stem 36, acting on lever 48, swings the latter about the fulcrum bolt 60to shift the lever 48 along the bolt 62 against the action of spring 66.It is understood at this juncture that the fluid pressure required toeffect this action is dependent upon the tension in spring 66 asadjusted through use of the nut 68, the setting being readilyascertained by observing the position of the washer 102 with respect tothe graduations 100. This movement of the lever 48 is transmitted to thebolt 96 and therefore to the lever 92, thereby actuating the switch 84so as to open or close an electric circuit.

As the pressure in fittings 28, port 24 and cavity 22 increases stillfurther to another preselected level, diaphragm 20 shifts the piston 42until it bottoms out in the recess 40, thereby moving the stem 44 withinthe bore 46 and with respect to the stem 36. Such inward movement of thestem 44 is transmitted to the lever 50 causing the latter to swing aboutthe fulcrum bolt 72 and shift along the bolt 74 against the action ofspring 76. The pressure required to effect this action is determined bythe tension in the spring 76 as adjusted by nut 78.

The inward movement of the lever 58 is transmitted to the bolt 98 andtherefore to the lever 94, actuating the switch 86 and thereby openingor closing a second electrical circuit.

Manifestly, precise spacing so as to assure depression and release ofthe actuating buttons of the switches 84 and 86 during swinging of thelevers 48 and 50 and therefore swinging of the corresponding levers 92and 94 may be made by manipulation of the bolts 96 and 98.

It is also important to note at this juncture that by virtue of the factthat the piston 42 bottoms out in the recess 40 and the piston 34bottoms out in the cavity 32, surge pressures are resistedby the plug 16so that the relatively high pressures will have no effect adversely uponany of the component parts of the pressure actuated device housed withinthe envelope 10.

There is presented therefore a highly sensitive instrument which sensestwo changes in pressure as to open or close the electrical switchingelements 84 and 86 when predetermined pressure points are reached. Thedevice is of course adaptable for use with either normally open ornormally closed switching elements and the setting may obviously be setfor actuation at any desired point on either rising or fallingpressures. The above explanation of settings to actuate on increasingpressures is therefore understood to be for illustrative purposes only.

in this connection then, while the adjustable range of the device isdetermined by the settings of the nuts 68 and 78, such range can beincreased or decreased still further by selections of springs 66 and 76capable of differing degrees of yieldable pressure on the levers 48 and50, all without adverse effect upon the diaphragm 20 because, as abovementioned, the pistons 34 and 42 remain freely movable when the fluidpressure is below the points of piston actuation.

Still another manner of changing the range of the device is to usepistons 34 and 42 of various sizes insofar as surface area is concerned,i.e., those areas thereof which face toward and are subjected to theaction of diaphragm 20. This may be done with devices that have greateror smaller overall dimensions or by substituting the pistons 34 and 42with other pistons wherein the relative sizes of such areas are chosento meet required uses.

While in the embodiment chosen for illustration there is provided buttwo switches 84 and 86 together with their corresponding actuatingassemblies and a common diaphragm type of sensor 22, the principlesherein disclosed may be followed to permit opening and closing of amultitude of switches within a single envelope, limited only by spacerequirements and choice of components such as to maintain reliability,accurateness, pressure ranges and other desired characteristics.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters patent is:

1. A pressure actuated device comprising:

a pair of levers each having a fulcrum about which the same moves;

resilient means for each lever respectively yieldably biasing the sametoward one end of its path of travel;

a switch associated with each lever respectively for actuation by itslever upon movement of the latter toward the opposite end of said pathof travel thereof; and

pressure sensitive structure for moving the levers to said opposite endsof their paths of travel,

said structure including a shiftable element for each lever respectivelyand a sensor common to the elements and adapted to shift the latter whenthe sensor is subjected to varying fluid pressures,

said resilient means yielding under different pressures exerted on saidsensor, said elements being reciprocable along a common axis with one ofthe elements surrounding the other of said elements.

2. A pressure actuated device as claimed in claim 1, said levers beingrelatively overlapped, one of the levers having a clearance opening forthe element of the other lever.

3. A pressure actuated device comprising:

a pair of elements 'reciprocable along a common axis with one of theelements surrounding the other of said elements;

a sensor common to the elements and adapted to shift the latter in onedirection when the sensor is subjected to varying fluid pressures;

resilient means for each element respectively yieldably biasing the samein the opposite direction,

said resilient means yielding under different pressures exerted on saidsensor; and

an electric switch for each element respectively disposed for actuationby the latter when shifted in said one direction.

4. A pressure actuated device as claimed in claim 3, each element havinga piston engageable at one face thereof by said sensor, each pistonbeing provided with an elongated stem extending from its opposite face,one of the stems having an external guide and a longitudinal boreconcentric to and reciprocably receiving the other stem.

5. A pressure actuated device as claimed in claim 4, said one stemhaving a cavity in said one face thereof for receiving the piston of theother stem.

1. A pressure actuated device comprising: a pair of levers each having afulcrum about which the same moves; resilient means for each leverrespectively yieldably biasing the same toward one end of its path oftravel; a switch associated with each lever respectively for actuationby its lever upon movement of the latter toward the opposite end of saidpath of travel thereof; and pressure sensitive structure for moving thelevers to said opposite ends of their paths of travel, said structureincluding a shiftable element for each lever respectively and a sensorcommon to the elements and adapted to shift the latter when the sensoris subjected to varying fluid pressures, said resilient means yieldingunder different pressures exerted on said sensor, said elements beingreciprocable along a common axis with one of the elements surroundingthe other of said elements.
 2. A pressure actuated device as claimed inclaim 1, said levers being relatively overlapped, one of the levershaving a clearance opening for the element of the other lever.
 3. Apressure actuated device comprising: a pair of elements reciprocablealong a common axis with one of the elements surrounding the other ofsaid elements; a sensor common to the elements and adapted to shift thelatter in one direction when the sensor is subjected to varying fluidpressures; resilient means for each element respectively yieldablybiasing the same in the opposite direction, said resilient meansyielding under different pressures exerted on said sensor; and anelectric switch for each element respectively disposed for actuation bythe latter when shifted in said one direction.
 4. A pressure actuateddevice as claimed in claim 3, each element having a piston engageable atone face thereof by said sensor, each piston being provided with anelongated stem extending from its opposite face, one of the stems havingan external guide and a longitudinal bore concentric to and reciprocablyreceiving the other stem.
 5. A pressure actuated device as claimed inclaim 4, said one stem having a cavity in said one face thereof forreceiving the piston of the other stem.